Problem: Express your answer as a mixed number simplified to lowest terms. $15\dfrac{13}{20}-6\dfrac{2}{8} = {?}$
Solution: Separate the whole numbers from the fractional parts: $= {15} + {\dfrac{13}{20}} - {6} - {\dfrac{2}{8}}$ Bring the whole numbers together and the fractions together: $= {15} - {6} + {\dfrac{13}{20}} - {\dfrac{2}{8}}$ Subtract the whole numbers: $=9 + {\dfrac{13}{20}} - {\dfrac{2}{8}}$ Simplify each fraction: $= 9 + {\dfrac{13}{20}} - {\dfrac{1}{4}}$ Find a common denominator for the fractions: $= 9+\dfrac{13}{20}-\dfrac{5}{20}$ Subtract the fractions: $= 9+\dfrac{8}{20}$ Combine the whole and fractional parts into a mixed number: $= 9\dfrac{8}{20}$ Simplify to lowest terms: $= 9\dfrac{2}{5}$